class Abc {
    constructor(args) {
        //super(args);
        this.age = 10;
    }

    process2() {
        console.log('p2');
    }

    process() {
        this.age = 12;
        this.process2();
        setTimeout(function () {
            this.age = 45;
            console.log('aaa');
            console.log(this.age);
        }, 1200);
    }
}

var abc = new Abc();
abc.process();
console.log(abc.age);
setTimeout(function () {
    console.log(abc.age);
}, 1200);